North Bay Resources Inc (NBRI)

[Nickybee]

Assuming mortgage extention:

Note: majority of the mineralized body contains sub economic mineralization; quite often, more than 90% of the recoverable gold is found in 5 – 10% of the volume of the mineralized body. This makes conventional geostatistical estimation of the grade or tenor of the mineralized bodies extremely difficult if not impossible. Fortunately, the distribution of the pockets or bunches of coarse gold is controlled by various geologic phenomenon, which are for the most part predictable. The main geologic phenomena responsible for localizing coarse gold in the Ruby Mine are:
1. intersections of bedrock quartz vein systems with buried placer channels
2. abrupt changes in direction of the placer channels (often related to 1.)
3. abrupt changes in the gradient of the placer channel
4. intersections of quartz veins with other veins or geological structures (vein deposits)
5. areas where the dip of the vein abruptly flatten out(rolls)
These geologic phenomena can be predicted, if the detailed geology of the mine is known. Once the overall geology of the Ruby property was defined, the general course of various buried placer channels could be predicted, as well as the probable intersections of these channels with various quartz vein systems (projected along strike from exposures in mine workings).
A rather lengthy discussion is presented on the difficulties of sampling and grade projection for California’s drift mines (of which the Ruby Mine is one of the more famous) in BLM Technical Bulletin 4, Placer Examination, Principles and Practice. An excerpt from the Manual in Section 7 – When Sampling Fails – (p 68) states:
Where factual sample data cannot be obtained without extensive and costly explorations, which except in isolated cases will never be made, authentic production records will generally be found a useful source of information. And even when the actual records are not available, it may be possible to obtain enough statistical information from state mining bureau reports or other government publications to ascertain the past production of better-known mining districts and to appraise their remaining potential. To varying degrees, this type of statistical data can be applied to individual properties.

The BOLD phrases control the mine

Source : Ruby Mine 43-101 report pages 29,30